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class M1
class M2 extends M1
class M3 extends M2
trait S1 { val q = new M1 ; val q1: q.type = q }
trait S2 { val q = new M2 ; val q2: q.type = q }
class B extends S1 with S2 {
override val q = new M3
val q3: q.type = q
var x1: B.super[S1].q1.type = null
var x2: B.super[S2].q2.type = null
var x3: B.this.q3.type = null
x1 = x1
x1 = x2
x1 = x3
x2 = x1
x2 = x2
x2 = x3
x3 = x1
x3 = x2
x3 = x3
x1 = q1
x1 = q2
x1 = q3
x2 = q1
x2 = q2
x2 = q3
x3 = q1
x3 = q2
x3 = x3
}
class C extends S1 with S2 {
override val q = new M3
val q3: q.type = q
// x1's type and x2's type are incompatible
// x3's is assignable to x1 or x2, but not vice versa
var x1: C.super[S1].q.type = null
var x2: C.super[S2].q.type = null
var x3: C.this.q.type = null
x1 = x1
x1 = x2 // fail
x1 = x3
x2 = x1 // fail
x2 = x2
x2 = x3
x3 = x1 // fail
x3 = x2 // fail
x3 = x3
x1 = q1
x1 = q2
x1 = q3
x2 = q1
x2 = q2
x2 = q3
x3 = q1
x3 = q2
x3 = x3
x1 = q
x1 = super[S1].q
x1 = super[S2].q // fail
x2 = q
x2 = super[S1].q // fail
x2 = super[S2].q
x3 = q
x3 = super[S1].q // fail
x3 = super[S2].q // fail
}
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